• 제목/요약/키워드: Membrane integrity

검색결과 272건 처리시간 0.032초

Evaluation of tissue ingrowth and reaction of a porous polyethylene block as an onlay bone graft in rabbit posterior mandible

  • Sosakul, Teerapan;Tuchpramuk, Pongsatorn;Suvannapruk, Waraporn;Srion, Autcharaporn;Rungroungdouyboon, Bunyong;Suwanprateeb, Jintamai
    • Journal of Periodontal and Implant Science
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    • 제50권2호
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    • pp.106-120
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    • 2020
  • Purpose: A new form of porous polyethylene, characterized by higher porosity and pore interconnectivity, was developed for use as a tissue-integrated implant. This study evaluated the effectiveness of porous polyethylene blocks used as an onlay bone graft in rabbit mandible in terms of tissue reaction, bone ingrowth, fibrovascularization, and graft-bone interfacial integrity. Methods: Twelve New Zealand white rabbits were randomized into 3 treatment groups according to the study period (4, 12, or 24 weeks). Cylindrical specimens measuring 5 mm in diameter and 4.5 mm in thickness were placed directly on the body of the mandible without bone bed decortication, fixed in place with a titanium screw, and covered with a collagen membrane. Histologic and histomorphometric analyses were done using hematoxylin and eosin-stained bone slices. Interfacial shear strength was tested to quantify graft-bone interfacial integrity. Results: The porous polyethylene graft was observed to integrate with the mandibular bone and exhibited tissue-bridge connections. At all postoperative time points, it was noted that the host tissues had grown deep into the pores of the porous polyethylene in the direction from the interface to the center of the graft. Both fibrovascular tissue and bone were found within the pores, but most bone ingrowth was observed at the graft-mandibular bone interface. Bone ingrowth depth and interfacial shear strength were in the range of 2.76-3.89 mm and 1.11-1.43 MPa, respectively. No significant differences among post-implantation time points were found for tissue ingrowth percentage and interfacial shear strength (P>0.05). Conclusions: Within the limits of the study, the present study revealed that the new porous polyethylene did not provoke any adverse systemic reactions. The material promoted fibrovascularization and displayed osteoconductive and osteogenic properties within and outside the contact interface. Stable interfacial integration between the graft and bone also took place.

Effect of Excipients on the Stability and Transport of Recombinant Human Epidermal Growth Factor (rhEGF) across Caco-2 Cell Monolayers

  • Kim, In-Wha;Yoo, Ho-Jung;Song, Im-Sook;Chung, Youn-Bok;Moon, Dong-Cheul;Chung, Suk-Jae;Shim, Chang-Koo
    • Archives of Pharmacal Research
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    • 제26권4호
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    • pp.330-337
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    • 2003
  • The effect of sixteen excipients on the transport of recombinant human epidermal growth factor (rhEGF) across Caco-2 cell monolayers was examined at $37^{\circ}C$. The apparent apical to basolateral (A-B) permeability ($P_{app}$) of 30 $\mu$ M rhEGF was $8.15\times 10^{-7}$ cm/sec, indicative of a poor level of absorption in the GI tract. The Papp was 1.7- and 6.3-fold greater than the $P_{app}$ in the basolateral to apical (B-A) direction and the A-B permeability of mannitol, respectively, and decreased dramatically to a negligible level at $4^{\circ}C$, consistent with a receptor mediated transcytosis of rhEGF. The stability of rhEGF was very poor, undergoing more than 85% degradation in 2 h in the transport medium at $37^{\circ}C$. A significant increase in the $P_{app}$ could be achieved by the addition of certain excipients, as exemplified by 23, 21, 20 and 16-fold increases, in the presence of sodium taurochenodeoxycholate (NaTCDC), sodium taurodeoxycholate (NaTDC), sodium glycodeoxycholate (NaGDC) and sodium laurylsulfate (SLS) (all at a concentration of 1 % w/v), respectively. A significant increase in stability could also be achieved by the addition of some of the excipients, as represented by 1 % SLS, which nearly completely stabilized the rhEGF. Unfortunately, however, an increase in the $P_{app}$ of rhEGF could not be achieved without a simultaneous and extensive decrease in the integrity of the cell membranes. Thus, more efficient excipients, that specifically enhance the permeation of rhEGF and do not alter the membrane integrity, should be pursued in order to safely enhance the permeation of rhEGF.

망막 색소상피세포에서 산화성 세포 손상과 미토콘드리아기능 저해에 미치는 NS 1619의 보호 효과 (The Ca2+-activated K+ (BK) Channel-opener NS 1619 Prevents Hydrogen Peroxide-induced Cell Death and Mitochondrial Dysfunction in Retinal Pigment Epithelial Cells)

  • 강재훈;우재석
    • 생명과학회지
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    • 제27권11호
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    • pp.1349-1356
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    • 2017
  • $K^+$ 통로 개방제들은 심근, 뇌, 골격근 등에서 세포막 혹은 미토콘드리아 내막에 존재하는 큰 전도성의 $Ca^{2+}$-의 존성 $K^+$ (BK) 통로 및 ATP-조절성 $K^+$ 통로(ATP-sensitive $K^+$ channels, $K_{ATP}$)에 작용하여 허혈성 혹은 산화성 세포 손상을 완화하는 효과가 있는 것으로 보고되어 있다. 본 연구에서는 망막 색소 상피세포주인 ARPE-19 세포를 실험 모델로 하여 큰 전도성의 BK 통로 개방제인 NS 1619가 유사한 보호 효과를 나타낼 수 있는지, 또한 그 작용기전이 무엇인지를 확인하고자 하였다. AREE-19 세포를 여러 형태의 산화 스트레스에 노출시켜 세포 손상을 유발하고 그 손상의 정도 및 이에 미치는 NS 1619의 효과를 trypan blue 배출능, Tunel 염색 분석을 통하여 측정하였다. NS 1619는 여러 형태의 산화 스트레스에 의한 괴사성 및 apoptosis에 의한 세포 손상을 효과적으로 방지하였으며 그 보호 효과는 BK 통로 봉쇄제인 paxilline 의해 차단되었다. NS 1619는 $H_2O_2$에 의한 세포내 ATP 고갈을 현저히 완화시켰으며, 또한 MTT 환원능으로 측정한 미토콘드리아의 기능을 보호하는 효과를 보였다. 유세포형광 분석법을 이용한 실험에서 NS 1619는 $H_2O_2$에 의한 미토콘드리아 막전압의 소실을 유의하게 방지하였다. 이상의 결과들을 종합하면 NS 1619는 망막 색소 상피세포에서 산화성 세포 손상을 방지하는 효과를 나타내며 그 기전에 미토콘드리아 기능에 대한 보호 작용이 연관되어 있는 것으로 사료된다.

Luteinizing hormone beta gene polymorphism and its effect on semen quality traits and luteinizing hormone concentrations in Murrah buffalo bulls

  • Reen, Jagish Kour;Kerekoppa, Ramesha;Deginal, Revanasiddu;Ahirwar, Maneesh Kumar;Kannegundla, Uday;Chandra, Satish;Palat, Divya;Das, Dayal Nitai;Kataktalware, Mukund Amritrao;Jeyakumar, Sakthivel;Isloor, Shri krishna
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권8호
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    • pp.1119-1126
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    • 2018
  • Objective: Present investigation was aimed to study the Single Nucleotide Variants of the luteinizing hormone beta ($LH{\beta}$) gene and to analyze their association with the semen quality (fresh and post-thawed frozen semen) and luteinizing hormone (LH) concentrations in Murrah buffalo bulls. Methods: Polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) and Sanger sequencing method is used to study genetic variability in $LH{\beta}$ gene. LH assay was carried out using enzyme-linked immunosorbent assay method. A fixed general linear model was used to analyze association of single nucleotide polymorphism (SNP) of $LH{\beta}$ gene with semen quality in 109 and LH concentrations in 80 Murrah bulls. Results: $LH{\beta}$ gene was found to be polymorphic. Total six SNPs were identified in $LH{\beta}$ gene g C356090A, g C356113T, g A356701G, g G355869A, g G356330C, and g G356606T. Single Stranded Conformational Polymorphism variants of pattern 2 of exon 1+pattern 2 of exon 2+pattern 1 of exon 3 had highly significant (p<0.01) effect on sperm concentration (million/mL), percent mass motility, acrosome integrity and membrane integrity in fresh and frozen semen whereas significant (p<0.05) effect was observed on percent live spermatozoa. SSCP variants of pattern 2 of exon 1+pattern 2 of exon 2+pattern 1 of exon 3 had highly significant (p<0.01) effect on luteinizing hormone concentrations too. Conclusion: The observed association between SSCP variants of $LH{\beta}$ gene with semen quality parameters and LH concentrations indicated the possibilities of using $LH{\beta}$ as a candidate gene for identification of markers for semen quality traits and LH concentrations in Murrah buffaloes.

Agrobacterium tumefaciens Spheroplast의 연초엽육 Protoplast내 도입에 관한 세포학적 연구 (Cytological Study of the Introduction of Agrobacterium tumefaciens Spheroplasts into Nicotiana tabacum Protoplasts)

  • 김정희;구용범;이기영
    • Journal of Yeungnam Medical Science
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    • 제2권1호
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    • pp.175-181
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    • 1985
  • Polyethylene glycol(PEG) 처리에 의한 Agrobacterium tumefaciens spheroplast와 연초 엽육 protoplast의 상호작용을 연구하기 위하여, 효소적 방법으로 분리한 연초엽육 protoplast와 carbenicillin 및 lysozyme의 처리에 의해 제조된 Agrobacterium tumefaciens ATCC 15955 spheroplast를 섞어서 polyethylene glycol (PEG) 및 high pH-high $Ca^{2+}$ buffer를 처리한 후 시료를 취하여 전자현미경으로 관찰한 결과, spheroplast는 초기 단계에서 protoplast membrane에 부착하고, 시간이 경과함에 따라 endocytosis에 의해 protoplast의 세포질 내부로 도입된 다음, 점차로 그 형체(cell integrity)가 파괴되어지는 것을 관찰할 수 있었다. 이러한 관찰 결과로부터 spheroplast는 polyethylene glycol(PEG)에 의해 protoplast내부로 endocytosis되어짐을 알 수 있었다.

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Antifungal Activity of Silver Salts of Keggin-Type Heteropolyacids Against Sporothrix spp.

  • Mathias, Luciana Da Silva;Almeida, Joao Carlos De Aquino;Passoni, Luis Cesar;Gossani, Cristiani Miranda David;Taveira, Gabriel Bonan;Gomes, Valdirene Moreira;Vieira-Da-Motta, Olney
    • Journal of Microbiology and Biotechnology
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    • 제30권4호
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    • pp.540-551
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    • 2020
  • Sporotrichosis is a chronic and subacute mycosis causing epidemiological outbreaks involving sick cats and humans in southeastern Brazil. The systemic disease prevails in cats and in humans, with the symptoms restricted to the skin of immunocompetent individuals. Under these conditions, the prolonged treatment of animals and cases of recurrence justify the discovery of new treatments for sporotrichosis. This work addresses the antifungal activity of silver salts of Keggin-type heteropolyacid salts (Ag-HPA salts) such as Ag3[PW12O40], Ag6[SiW10V2O40], Ag4[SiW12O40] and Ag3[PMo12O40] and interactions with the antifungal drugs itraconazole (ITC), terbinafine (TBF) and amphotericin B (AMB) on the yeast and mycelia forms of Sporothrix spp. Sporothrix spp. yeast cells were susceptible to Ag-HPA salts at minimum inhibitory concentration (MIC) values ranging from 8 to 128 ㎍/ml. Interactions between Ag3[PW12O40] and Ag3[PMo12O40] with itraconazole and amphotericin B resulted in higher antifungal activity with a reduction in growth and melanization. Treated cells showed changes in cell membrane integrity, vacuolization, cytoplasm disorder, and membrane detachment. Promising antifungal activity for treating sporotrichosis was observed for the Ag-HPA salts Ag3[PMo12O40] and Ag3[PW12O40], which have a low cost, high yield and activity at low concentrations. However, further evaluation of in vivo tests is still required.

Curcumin Attenuates Hydrogen Peroxide Induced Oxidative Stress on Semen Characteristics during In Vitro Storage of Boar Semen

  • Jang, Hyun-Yong;Kim, Young-Han;Cheong, Hee-Tae;Kim, Jong-Taek;Park, In-Chul;Park, Choon-Keun;Yang, Boo-Keun
    • Reproductive and Developmental Biology
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    • 제33권2호
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    • pp.99-105
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    • 2009
  • Curcumin is a major active component of the food flovour tumeric. It has been used for the treatment of many diseases such as inflammatory and infectious diseases, cancer and other disease due to its antioxidant properties. Curcumin is a powerful scavenger of many free radicals such as superoxide anion, hydroxyl radical and nitric oxide. The objective of this study was to investigate the antioxidative effects of curcumin against hydrogen peroxide on semen quality during in vitro storage of boar semen. The sperm treated with different concentration of curcumin (1, 5 and 10 ${\mu}M$) in the presence or absence of hydrogen peroxide (250 ${\mu}M\;H_2O_2$) were incubated for 3, 6 and 9 hr at $37^{\circ}C$ and analyzed sperm characteristics such as motility, membrane integrity (MI), lipid peroxidation (LPO), reactive oxygen species (ROS) and DNA fragmentation (DF). The sperm motility and MI in $H_2O_2$ treated group ($47.8%{\pm}6.8$ and $24.8%{\pm}2.2$) were significantly decreased when compare to curcumin treated group ($79.8%{\pm}2.7$ and $34.6%{\pm}1.0$, respectively) irrespective of incubation periods(p<0.05). The LPO of spermatozoal plasma membrane was measured by thiobarbituric acid (TBA) reactions for malondialdehyde (MDA), MDA level in control ($11.6{\pm}0.6\;nmol/L{\times}10^6$) and curcumin groups ($10.7{\pm}0.3\;nmol/L{\times}10^6$) were lower than those of curcumin plus $H_2O_2$ ($17.1{\pm}0.8\;nmol/L{\times}10^6$) or $H_2O_2$ group ($22.5{\pm}1.9\;nmol/L{\times}10^6$) from 3 to 9 hr incubation periods. The DF by sperm chromatin dispersion (SCD) test and ROS production measured by 2',7'-dichlorofluorescein (DCF) fluorescence intensity were no significantly difference through all experimental groups (p>0.05). Correlation among evaluation methods for sperm quality, motility vs MI and DF vs ROS was positively correlated while motility vs DF and ROS vs LPO were negatively correlated in all treatment groups. These results demonstrate that curcumin can effectively improve the sperm quality during in vitro storage of boar semen through its hydrogen peroxide scavenging mechanism as an antioxidant.

Cellular Zn depletion by metal ion chelators (TPEN, DTPA and chelex resin) and its application to osteoblastic MC3T3-E1 cells

  • Cho, Young-Eun;Lomeda, Ria-Ann R.;Ryu, Sang-Hoon;Lee, Jong-Hwa;Beattie, John H.;Kwun, In-Sook
    • Nutrition Research and Practice
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    • 제1권1호
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    • pp.29-35
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    • 2007
  • Trace mineral studies involving metal ion chelators have been conducted in investigating the response of gene and protein expressions of certain cell lines but a few had really focused on how these metal ion chelators could affect the availability of important trace minerals such as Zn, Mn, Fe and Cu. The aim of the present study was to investigate the availability of Zn for the treatment of MC3T3-E1 osteoblast-like cells and the availability of some trace minerals in the cell culture media components after using chelexing resin in the FBS and the addition of N,N,N',N'-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN, membrane-permeable chelator) and diethylenetriaminepentaacetic acid (DTPA, membrane-impermeable chelator) in the treatment medium. Components for the preparation of cell culture medium and Zn-treated medium have been tested for Zn, Mn, Fe and Cu contents by atomic absorption spectrophotometer or inductively coupled plasma spectrophotometer. Also, the expression of bone-related genes (ALP, Runx2, PTH-R, ProCOL I, OPN and OC) was measured on the cellular Zn depletion such as chelexing or TPEN treatment. Results have shown that using the chelexing resin in FBS would significantly decrease the available Zn (p<0.05) $(39.4{\pm}1.5{\mu}M\;vs\;0.61{\pm}10.15{\mu}M)$ and Mn (p<0.05) $(0.74{\pm}0.01{\mu}M\;vs\;0.12{\pm}0.04{\mu}M)$. However, levels of Fe and Cu in FBS were not changed by chelexing FBS. The use of TPEN and DTPA as Zn-chelators did not show significant difference on the final concentration of Zn in the treatment medium (0, 3, 6, 9, $12{\mu}M$) except for in the addition of higher $15{\mu}M\;ZnCl_2$ which showed a significant increase of Zn level in DTPA-chelated treatment medium. Results have shown that both chelators gave the same pattern for the expression of the five bone-related genes between Zn and Zn+, and TPEN-treated experiments, compared to chelex-treated experiment, showed lower bone-related gene expression, which may imply that TPEN would be a stronger chelator than chelex resin. This study showed that TPEN would be a stronger chelator compared to DTPA or chelex resin and TPEN and chelex resin exerted cellular zinc depletion to be enough for cell study for Zn depletion.

Effect of Double Replacement of L-Pro, D-Pro, D-Leu or Nleu in Hydrophobic Face of Amphipathic α-Helical Model Antimicrobial Peptide on Structure, Cell Selectivity and Mechanism of Action

  • Shin, Song Yub
    • Bulletin of the Korean Chemical Society
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    • 제35권11호
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    • pp.3267-3274
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    • 2014
  • In order to investigate the effects of the double replacement of $\small{L}$-Pro, $\small{D}$-Pro, $\small{D}$-Leu or Nleu (the peptoid residue for Leu) in the hydrophobic face (positions 9 and 13) of amphipathic ${\alpha}$-helical non-cell-selective antimicrobial peptide $L_8K_9W_1$ on the structure, cell selectivity and mechanism of action, we synthesized a series of $L_8K_9W_1$ analogs with double replacement of $\small{L}$-Pro, $\small{D}$-Pro, $\small{D}$-Leu or Nleu in the hydrophobic face of $L_8K_9W_1$. In this study, we have confirmed that the double replacement of $\small{L}$-Pro, $\small{D}$-Pro, or Nleu in the hydrophobic face of $L_8K_9W_1$ let to a great increase in the selectivity toward bacterial cells and a complete destruction of ${\alpha}$-helical structure. Interestingly, $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu preferentially interacted with negatively charged phospholipids, but unlike $L_8K_9W_1$ and $L_8K_9W_1$-$\small{D}$-Leu, they did not disrupt the integrity of lipid bilayers and depolarize the bacterial cytoplasmic membrane. These results suggested that the mode of action of $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu involves the intracellular target other than the bacterial membrane. In particular, $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu had powerful antimicrobial activity (MIC range, 1 to $4{\mu}M$) against methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Pseudomonas aeruginosa (MDRPA). Taken together, our results suggested that $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu with great cell selectivity may be promising candidates for novel therapeutic agents, complementing conventional antibiotic therapies to combat pathogenic microorganisms.

Follow-up of Exogenous DNA by Sperm-mediated Gene Transfer via Liposome

  • Cho, Hwang-Yun;Chung, Ki-Hwa;Kim, Jin-Hoi
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권10호
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    • pp.1412-1421
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    • 2002
  • To examine the feasibility of using a sperm vector system for gene transfer, we have investigated the binding and the uptaking of foreign DNA into the sperm nucleus by PCR, in situ hybridization and LSC. We have also examined the transportation of exogenous DNA into oocytes by immunofluorescene via PCR. Sperm cells were incubated with DNA/liposome complexes (1:4 ratio) in fertilization medium with BSA or without BSA. In situ hybridization demonstrated that the transfection rate of sperm cells with and without BSA was 41 and 68% respectively, when the cells were treated with liposome/DNA complexes and 13% for DNA alone. LSC analysis showed that the binding of exogenous DNA was greatly reduced by DNase I treatment which digests DNA bound onto spermatozoa, suggesting that some of the DNA was internalized into the sperm membrane. To find out whether transfected DNA was internalized into sperm intracytomembrane, sperm DNA was amplified by inverse PCR. No PCR products were detected from sperm cells, indicating that the foreign DNA was simply bound onto the sperm membrane. To investigate transfer rates of exogenous DNA into oocytes via sperm cells, we used immunofluorescene method to follow the distribution of foreign DNA via spermatozoa: a few exogenous DNA was located in the cytoplasm of early embryos (13/60, 21.7% for DNA+/liposome+/BSA) and was not located in the pronucleus and/or nucleus. These results suggest that most of the transfected sperm cells could carry the foreign DNA into the egg by in vitro fertilization, but that the transferred DNA is degraded in the developing embryos without stable integration into the zygote genome. Therefore, we have directly injected with transfected sperm cell into oocyte cytoplasm and observed that some of the exogenous DNA was detected in preimplantation embryonic cytoplasm and expressed at preimplantation stages, suggesting that exogenous DNA in early zygote has their integrity. In this study, we have not identified a noble mechanism that interfering transportation of foreign DNA into zygote genome via spermatozoa. Our data, however, demonstrated that inverse PCR and immunofluorescene methods would be used as a new tool for follow-up of gene distribution in oocyte via sperm cells.